Field of the Invention
The present invention relates to a skin external composition containing a red yeast rice extract, and more particularly, to a skin external composition containing a red yeast rice extract which can increase the production of loricrin in keratinocytes to promote keratinization and to strengthen the skin barrier function, thereby exhibiting an excellent effect of improving skin moisturization.
Description of the Prior Art
The type of keratin that is expressed in keratinocytes is specific depending on the degree of differentiation of keratinocytes. Specifically, the K5/K14 keratin pair is expressed mainly in keratinocytes of the basal layer, and the K10/K1 keratin pair starts to be expressed in place of the K5/K14 keratin pair when keratinocytes migrate from the basal layer to the spinous layer. Loricrin is a protein that is expressed during the final differentiation of keratinocytes. It is required for forming stable keratin by differentiation of keratinocytes, and accounts for 70-85% of the mass of keratin. It has a domain that is rich in glutamine and lysine, which can participate in interpeptide cross-linking which is catalyzed by transglutaminase. In addition, it promotes the cross-linking between keratinocytes, thereby playing an important role in keratinization. Such loricrin binds to the cell membrane in the granular layer to form a protein, and thus is used as a marker in tracking the differentiation of keratinocytes.
Thus, in order to form the horny layer so as to strengthen the skin barrier that prevents the loss of water from skin tissue while promoting the retention of water in skin tissue to thereby prevent skin aging and protect the skin from external environmental changes such as atmospheric drying, UV light and various pollutants, the development of a skin moisturizing substance that promotes the expression of loricrin is required.